Mechanical handling and gripping apparatus



Dec. 15, 1964 J. E. KENNETT 3,161,303

MECHANICAL HANDLING AND GRIPPING APPARATUS Filed March 6, 1961 5 Sheets-Sheet l Dec. 15, 1964 J. E. KENNETT 3,161,308

MECHANICAL HANDLING AND GRIPPING APPARATUS Filed March 6, 1961 5 Sheets-Sheet 2 Dec. 15, 1964 J. E. KENNETT MECHANICAL HANDLING AND GRIPPING APPARATUS 5 Sheets-Sheet 3 Filed March 6, 1961 Dec. 15, 1964 J. E. KENNETT 3,161,308

MECHANICAL HANDLING AND GRIPPING APPARATUS Filed March 6, 1961 5 Sheets-Sheet 4 Dec. 15, 1964 J. E. KENNETT 3,161,308

MECHANICAL HANDLING AND GRIPPING APPARATUS Filed March 6, 1961 5 Sheets-Sheet 5 United States Patent 3,161,308 MECHANKUAL HANlJLiNG AND GRiPPlN'G APPARATUS John Engiand Kennett, St. Michaels Close, Bury St. Edmunds, England Filed Mar. 6, 1961, Ser. No. 93,467 Claims priority, application Great Britain Mar. 7, H60 9 Claims. (Ci. 214-447) This invention relates to apparatus for the mechanical handling of materials by a gripping process and is particularly, although not exclusively, for use in connection with an agricultural or industrial tractor.

The present invention accordingly consists in a load gripping device for loads such as bales and conatiners. The device comprises a pair of arms connected to a frame in such a manner as to be able to pivot about vertical axis and about horizontal axis. Means are provided for causing the arms first to squeeze opposite sides of a load and then to be tilted upwards.

The invention will now be described, by way of example, with reference to the, accompanying diagrammatic drawings in which:

FIGURE 1 is a side elevation of mechanical handling apparatus according to the present invention.

FIGURE 2 is a part plan view of the apparatusshown in FIGURE 1; and

FIGURE 3 is a rear perspective view of modified mechanical handiing apparatus according to the present invention.

FIGURE 3a shows the detached right-hand arm of the apparatus shown in FIGURE 3.

FIGURE 3b is a side view of the apparatus shown in FIGURES 3 and 3a when attached to a rigid frame, the frame being similar to that shown in FIGURES 1 and 2.

FIGURE 30 is a side view of the apparatus shown in FIGURES 3 to 3.) after the load has been gripped and tilted.

FIGURE 4 is a side elevation of further modified mechanical handling apparatus according, to the present invention.

FIGURE 4a is a side view of the apparatus shown in FIGURE 4 after the load has been gripped and the arms tilted upwards.

FfGURE 4b is a plan view of part of the apparatus shown in FIGURE 4 showing the mounting of one of its pivoting hands on the corresponding gripping arms.

Referring firstly to FIGURES 1 and 2, as shown, there are provided load engaging arms I mounted on a subframe 2 adapted to be secured to a rigid frame 8 such as is described in my British patent specification No. 92,218 suitable for attachment to the arms of a tractor mounted hydraulic loader or three-point linkage of a tractor.

The sub-frame comprises a pair of vertically disposed plates 3 interconnected at their forward ends by cross bars 4 and 5 rigidly secured to the upper and lower corners of the plates 3. The upper rear edges of the plates are rockably carried by a bar 5 passing through apertures in the plates 3 and through lugs 7 on the rigid frame 8. The cross bars 4 and 5 are themselves interconnected by vertical ties 9 (FIGURE 3) constituting a fender. The lower cross bar 5 is provided at each end with rearwardly projecting pieces 10, which, as will hereinafter be described are capable of being bolted to the rigid frame 8 in order to prevent rocking movement of the sub-frame 2 about the bar 6. The load engaging arms 1, which rigidly carry vertical axes on the sub-frame 2, are mounted so that they can swing about vertical axes in relation to the sub-frame 2. The pillars 11 each carry a bracket 12 which is pivotally mounted on a vertical pin 13 itself Patented Dec. 15, 1964 mounted between the cross bars 4 and 5, the pins 13 constituting the rocking axes of the load gripping arms 1.

At their free ends the arms I carry load engaging members or plates 14, hereinafter referred to as hands, mounted on vertical pins 15. Conveniently the hands 14 are maintained substantially parallel to one another by means of a parallel linkage arrangement (not shown in FIGURES l and 2). The brackets 12 provided on the pillars 11 each carry a vertically disposed roller or antifriction means 17 adapted to engage a horizontally disposed rolier 18 as shown in FIGURE 1. The rollers 18 are carried by brackets l mounted on a cross piece 20 carried by arms 21. The arms 21 at their ends remote from the cross piece 2% are pivotally carried by the bar 6. A hydraulic jack (not shown) carried by the rigid frame 8 is operatively associated with a cross bar 22 interconnecting the arms 21, the arrangement being such that extension of the jack moves the arms 21 to the right as seen in FIGURE 1.

A pair of vertical tubular pillars 23 are mounted at their free ends on the upper cross bar 4. The pillars 23 carry lugs 24 upon which a pair of bell cranks 25, 26 are pivotally mounted by pins 27. The pivotal mounting of the arms 25, 26 may be adjusted by locating the pins 27 in any of apertures 28 in the lugs 24. The arms 25, 26 will hereinafter be referred to as load steadying arms.

In operation, when it is desired to pick up a load, for example, two pairs of bales of straw, one pair resting on top of the other, the loading vehicle is advanced until the hands 14 lie on. each side of the lower pair of bales as in FIGURE 2 and the load steadying arms 25, 26 lie against the upper pair of bales. The hydraulic jack is now extended to urge the rollers 18 forward against the rollers 17 and due to the pivotal mounting of the load gripping arms with respect to the rollers, the former are urged inwards and the hands 14 thus grip the lower bales.

Continued extension of the jack causes the sub-frame 2 to rock about the bar 6 so as to raise the load gripping arms 1 upwards from the ground. Upward movement of the arms 1 and thus of the lower bales causes the upper bales to slip backwards into engagement with the shorter arms 26 of the bell crank load steadying arms so as to cause the arms 25 to engage the sides of the upper bales and to hold them in position during maneuvering of the loading vehicle.

The arrangement is such that the pressure exerted on the sides of the lower part of the load is not greatly in excess of the total weight of the load and the apparatus can therefore safely handle empty crates and the like. The extension of the jack achieves the three objects of gripping the load, tilting it backwards for stability in the longitudinal plane so that it cannot fall forward if the loading vehicle is driven downhill or the brakes applied, and steadying the load in the lateral plane so that the bales cannot fail sideways.

Once the necessary minimum pressure needed to grip the load securely has been applied the sub-frame will start tilting backwards. The wider the load the greater the degree of possible backward inclination of the sub frame. When no load is encountered by the gripping arms the bar 2t) will engage the vertical plates 3 and the remaining stroke of the jack will be expanded solely on tilting the sub-frame. Where, however, very strong gripping is required projecting pieces 10 may be bolted at 29 to the rigid frame 8 to prevent tilting of the subframe, so that the force exerted by the extension of the jack is expended solely upon the gripping arms 1.

Referring now to FIGURES 3, 3a, 3b, and 30 this arrangement is similar to that described above with re spect to FIGURES 1 and 2, like parts being designated by like reference numerals. Howevenin this arrangement the load gripping arms 1 are'mounted on vertical pillars 36 (FIGURE 3 1) pivotally mounted at each end. 'by pins 13 in apertures 31 formed in brackets 32 secured to the cross bars 4 and 5; a plurality of apertures 31 laterallyspaced from one another are formed in the brackets 32 whereby the relative lateral spacing of the pillars I sub-frame 2' to rock about its pivot mounting on the bar I '6 and as the load gripping armsl are raised the hands and thus of the arms 1 may be adjusted to accommodate loads of different widths.

The Crossbars 4 and 5 are interconnected by vertical ties '9 and'by the plates 3 which carry lugs 33 pivotally The rearwardly projecting mounted on the bar 6. V brackets 12 of the apparatus-shown in FIGURES 1 and 2, which carry the vertical rollers 17 are replaced in this arrangement by inwardly projecting arms .34 secured to the upper ends of the pillars 36. The arms 21 are re- The pillars 23 are somewhat thinner than the pillars 2-3 in the first embodiment of the'invention. The upper lugs 24 of the first embodiment'are formed by the ends of a single horizontal girder 24' fixed to the top ends of pillars 23.

Although the hands 14 must be capable ofpivoting on their; mountings on the load gripping arms 1 in order to adjustth emselves in relation to the load being carried,

it is convenient to maintain them in a substantially parallel aspect to one another,- Thisis achieved by a parallel linkage arrangement, comprising an outwardly projecting lug 39 secured to each hand 14, and alight rod 40 pivoted to this lug. The pivot point of this rod 40 in relation to the hand 14 is about two inches from the pivot pin of the respective hand'14. The other end of the rod 40 is secured to one apex of a triangularbcll crank plate 41 pivotally mounted on a pin 41' and at its third apex is pivoted to a furtherfrod 42. As shown in FIGURE 3a the pin 41 is welded to the arms 1. 'The other end of the rod 42 passes through an eye in an upwardly projecting 'pin 43 and is spring-biased into a predetermined. position'with.

respect to the pin 43 by means of'com'pression springs 44 and 45.

the arms are opened and closed. a I Y Extension of the jack J whose ram R is connected to the lower ends'of the plates by means of cross beams '22, causes the plates to'pivot about the bar 6 andpull ,load gripping arms 1 inwards by means of the tension links 37.

As in 'the arrangement described with reference to FIGURES l and 2 extension of the jack will both cause the arms 1 to grip the lower bales and to incline the subframe constituted by parts 3, 4, 5, 23, 24 and 32.

FIGURES 4, 4a and 4b show a furthe'rembodiment of the invention'in which the gripping action is combined with means for tipping containers.

which are themselves pivotally mounted about vertical axes on pins 15 (see FIGURE 4b).

shown in FIGURE 3. The hands 14 carry lugs 47 which provide mountings for'ball and socket joints'48.

A 'pair of upward extensions or standards 49 are attached rigidly 'to the frame 8, these standards being con- In this manner the hands 14 are spring-' biased in'so that theyremainip'ar'allel to one another as Thenhands 14 are pivotally mounted abouthor'izonta'l axes on plates 46V Y the arms.

are caused to rotate about their horizontal axes until they assume the position shown in FIGURE 4a. It will be seen that in this position the container is rotated so as'to discharge its contents. 011 the'retraction stroke of the jack the action of lowering the arms 1 will cause the link 53 to pull the hands 14 into their horizontal position.

While I have described several embodiments of my invention so that those skilled in the art may gain the full advantages of ;it, it is to be understood that the embodiments are given by way of illustration only and that the monopoly I claim in'the United States is to be definedby the, gist and spirit of the appended claims.

What I claim is:' t i 1. A load gripping device for loads of the type described in the specification comprising a pair of generally horizontal arms, aframe to whichthe arms are connected so as to be able to pivot about vertical axes and so as to be able to pivot together about a horizontal axis generally perpendicular to, the arms, antifriction abutment means attached to the arms at a position vertically spaced from the horizontal axis, each antifriction'means being offset tom the axis of the arm to'which it is attached, means for engaging these antifrictionmeans so as to push the armstogetheron to a load between them and then, when the force'exerted on the load' has reached a certain value,'

to lift the load by tilting about the horizontal axis with 2., Thestructure as set forth in'claim 1 further comprising rollers constituting the antifriction means of the arms and further rollers arranged to be movedin a horizontal direction so as to engage the first-mentioned rollers. v 3. The structure as set forth in claim 2 in which the arms are provided with pivotaily mounted plates for engaging the sides of the load. I v I 4. The structure as set forth in claim 1 comprising bell crank levers mounted on the frame above the arms so as to be able'to pivot: about vertical axes; the arrangeinent being such that lifting and tilting. of the load carried by thearms causes the load to engage one arm each of the bell crank levers so as to cause the other'arms of the bell crank levers to grip the sides of the load and steady it. 5. A load. gripping device for loads of the type described inithe specification comprising a pair of generally'parallel and generally horizontal arms, a frame to which the arms are attachedso as to'be capable of pivotal movement about vertical axes in relation to the frame; and about a' horizontal axis. generally perpendicular to the arms, a linkageconnectedto; the'sides of the arms,v this linkage being arranged to receive a horizontally acting force and cause it to move the arms together against the sides of a load between them, and then, when the force thus exerted on the loadreaches a certain value, to lift'the load by Thetplates 46 are biased parallel 'to one another by means similar to those tilting thearms about the horizontal axis.

6. The structure as set forth in claim 5 further comprising load-engaging plates pivotally attached to the arms. 1 a a 7. The structure 'as set forth in claim 6 furthercomprising parallelogram linkages ensuring that the plates remain mutually parallel, and resilient means for allowing the plates to be pushed out of parallelism when an uneven load is gripped. V

8. A load handling device for loads of the type described comprising a frame, a pair of arms mounted on the frame .for. pivotal movement about vertical axis, and for pivotal movement about a horizontal axis generally perpendicular to the arms, means arranged to more the arms horizontally towards'eachother .to engage a load and then to tilt the arms about the. horizontal axis, load-engaging plates on the armsfor contacting the sides of the, load, these platesbeing attached to the arms so that they can pivot in relation to themabout horizontal axis, and means connecting the plates with thefrarne in such a nl'aiinerthatwh n the arnis aretilted, as already mentioned, the plates and the load are caused to swivel about a horizontal axis in relation to the arms.

9. The structure as set forth in claim 8, comprising a pair of inclined links, a further frame to which the previously mentioned frame is pivoted, an upward extension on the frame, the upper ends of the links being pivoted to this upward extension while the lower ends of the links are pivoted to the plates at positions spaced from the axis about which the plates are able to pivot in relation to the arms.

References Cited in the file of this patent UNITED STATES PATENTS Pope Dec. 5, Littefield Mar. 20, Wehr May 26, Salsas Feb. 5, Broersma Sept. 23, Kruse May 18, 

1. A LOAD GRIPPING DEVICE FOR LOADS OF THE TYPE DESCRIBED IN THE SPECIFICATION COMPRISING A PAIR OF GENERALLY HORIZONTAL ARMS, A FRAME TO WHICH THE ARMS ARE CONNECTED SO AS TO BE ABLE TO PIVOT ABOUT VERTICAL AXES AND SO AS TO BE ABLE TO PIVOT TOGETHER ABOUT A HORIZONTAL AXIS GENERALLY PERPENDICULAR TO THE ARMS, ANTIFRICTION ABUTMENT MEANS ATTACHED TO THE ARMS AT A POSITION VERTICALLY SPACED FROM THE HORIZONTAL AXIS, EACH ANTIFRICTION MEANS BEING OFFSET FROM THE AXIS OF THE ARM TO WHICH IT IS ATTACHED, MEANS FOR ENGAGING THESE ANTIFRICTION MEANS SO AS TO PUSH THE ARMS TOGETHER ON TO LOAD BETWEEN THEM AND THEN, WHEN THE FORCE EXERTED ON THE LOAD HAS REACHED A CERTAIN VALUE, TO LIFT THE LOAD BY TILTING ABOUT THE HORIZONTAL AXIS WITH THE ARMS. 